Also something that frustrated me a lot is that when browsing with the web browser on a computer, there is absolutely no way to share a link to a post.

For exemple there is a post with details about an event that will happen, when you look at available options: you can't click on it to go to a dedicated page like on LinkedIn, there is no option in the menu to have a shareable link. You can share with: someone on fb message, a group, your wall, things like that but no link.

But on the phone is it possible.

There's a perma-link when you click on the date of the post. But you're right, on the 'Share' button they have 5+ options, none of them is "copy link" or similar.